Is there a cause-and-effect connection between smoking cigarettes and lung cancer? One might well think so. We know that burning plant products produces smoke, which contains carcinogens, and other unpleasant compounds. We know that breathing smoke gets these materials deep into our lungs - which is why, in part, inhaling drugs can be an important option for drug delivery. We know that breathing smoke regularly, as in cigarette and other tobacco smoking, leads to increased rates of lung cancer, in a dose dependent manner.
Smoking led to increased tar delivery, more cellular changes in sputum, damage to alveolar macrophages, and increased abnormality in bronchial biopsies, with increased surrogate markers for lung cancer.
Around 90% of lung cancer cases are caused by tobacco smoking and a new study shows that tobacco smoke -- including secondhand smoke -- may also contribute to non-lung cancers more than previously thought.
The fact that lung and non-lung cancer death rates are almost perfectly associated means that smokers and nonsmokers alike should do what they can to avoid tobacco smoke.
Clearly, the best way to avoid cancer is not to smoke. While one cigarette is not likely to induce cancer, the accumulated risk of many cigarettes progressively increases the odds of disaster. 如果觉得多可以删减